The present invention relates to an athletic shoe providing superior support and high energy return, and more particularly, to an athletic shoe having a spring disposed in the heel that is prevented from bottoming out during compression.
There have been disclosed various athletic shoes incorporating a resilient member to provide for shock absorption and energy return. For example, U.S. Pat. No. 4,492,046 to Kosova describes a running shoe having a longitudinal slot in the sole extending from its back edge into the arch region and dividing the shoe sole into upper and lower segments. A spring wire in the slot decreases the velocity of the heel impact, and as the runner's weight shifts forward onto the ball and toes of the foot, the spring wire launches the runner into a comfortable stride.
U.S. Pat. No. 4,566,206 to Weber describes a shoe heel spring support wherein an undamped spring having multi-spring rates is provided in the heel support portion of a shoe for resiliently compressing under heel pressure against the ground and returning a substantial portion of the energy to the wearer's foot. The spring is formed of upper and lower leaflike legs that are integrally joined together at an acute angle whose apex is directed forwardly relative to the shoe. The V shaped spring first tends to compress together to a point where the intermediate leg contacts one of the outer legs, and at that point, increases the spring resistance so that the spring has two different spring rates. Thus, the reference attempts to receive and thereafter discharge the undamped energy put into the spring by the pressure of the wearer's heel against the ground.
U.S. Pat. No. 4,592,153 to Jacinto provides a heel construction for an athletic shoe capable of providing an optimal response for an individual wearing the shoe. The construction is adaptable to being permanently or detachably fixed to a shoe having an upper section and a detachably fixed to a shoe having an upper section and a sole section. The heel construction includes a generally Z-shaped resilient plate having an upper arm extending toward the toe area and a lower arm extending toward the periphery of the heel area of a shoe to which the construction is fixed.
Previous developments and designs, such as those referred to above, as well as other developments and designs of shoe sole constructions still exhibit various drawbacks or disadvantages of one type or another. For example, among the disadvantages such designs exhibit are high manufacturing cost, a limited degree of comfort, complex physical constructions, and in most instances, no optimal response. Furthermore, previous devices that utilize springs for shock absorption and energy return lack any structure to prevent the spring from bottoming out during compression.